Grid leak and condenser



Jan. 2l, 1930. w. DUBILIER GRID LEAK AND CONDENSER Filed Oct. 5l, 1925 Maz R E NM .Wm m

L M M 10 the terminals t 'free Fires aie-v1: mini a riferisci XVILTAB DUBLEE, GF NEVI ROCHELLE, NTM:

YQRK, ASSIGNGR @fR-ED LEAK AND CONDENSEM Application filed Ccteber 21, 1925.

. J. Istance element incorporated `with i" the invention is to A.

leek an d condenser iii i ihicli the pact`n` heid in secure combination, and

enen `etiie e ion with o which it is to be einiied.

' A further object et my invention is to proo in such a combination suitable ineefis for ding trie parts tirinly in operative relsi and protecting theiii against damage. li these and siicli other objects in vier! i y 1hereinfitter appear, iny invention coiis in the parts and combinations oi puits, hereinafter described and recited in tlie cleinis 5 with the understanding that the several necessary iiieinhers and elements oiE iny preferred constructions inziy be vsried in dimensions, torni and fmengenient- Without ded leek to have et i ig from the spill` and scope of the iiivention or elering ie iriiiciple thereof.

tl nt To ineke iny inve ion clear, have sho-:vii iii the ncconpeiiyiiig dre-Wings ing a part of this speciii ation, nieuiis for priictiene' the invention Without limiting* the inipio'ienents to the precise structurel details illustrated herein for purposes of explanation.

@n the dmv-:ings Figure l is e top plan of roved oi :fl leek and enser with av i it broken avvey Figure Q is i1 sectional vieu7 along the line 2--2 ot Fie'- iire l; Figure 3 is `top pien of e inodilicetieii and Figure Ll is e section ai view oii the line 1f-4 ot Figure 3. |The seine nunier'ls identity the saine parts throughout. Here-torero resisteiices for use with condensers connected to the grids of three-electrode viicuuin Jcubes, which resistances are, in neet, shun for the direct curi'eiiiJ component of the grid cui-rent, have been nitide es separate units.

tten such resistences ire mounted upon the condenser and put in parallel with it by ineens of special supports or clips attached to the terminals of the condenser. These methods of connection howeverv` perinit the condenser and grid leak to be anmected by vibre- Seral No. 6,93?.

tion, corrosion, and other dis ences; and experience deinoiistr -e cornoriition of the resistor or grid iii leal: virili Hw n A @n le 1 nl 1f. 1

Le eo LLenser is ini-,e i iiioie o. i

A'iousiy en externally located i ect to 'the elilects oi stin tien u resistance element enclo ot e condenser. ln :ny invent-i of uniformity ot resistance is in J igure l, the nunierels l indice electrical contact With the i i ments 2 of the body or stack of toY condens indicated es a Whole et 3. This as usuel of tii'ii plates of niiei fr suiiuble dielectric, placed between ductive elements 2, which muy be ioil of slightly smaller aree th On the loiver l c 3 a relatively thick rigid cove of suitable insulatingmateriel, for of belrelite is leid. Upon tlie other f" the stack, e thin .te G ot suitz ble ehi insulating rmt rial` rlhe plete 5 extended ends to which cleinps l are eliixed by rivets, fastening projecting' enes of the eieiiients 2 rinde cieiiips; the edges ll of the cleinps ove;Y laiping tiie edges of the top plate- 9, and cooperating With the bend clamp l) o secure J. l. t device he various parts oi" the entir gre-ther end under sufficient coliinression condenser of this type Without the soi incorporated, is shown iii my eopenc' n olicetion Serial No. 692869 iiied February i4, i924, Patent No. 1,575,045. Mai-d1 i ieee.

The clenip 10 although covering the greater part ofthe surface area between the clamp, l is nevertheless se erste-d therefrom alone 7 D its opposite edges by spaces oi suliicient width. Resist nce element 8 may be a thin strip o dried card board coated on one side with a thin slightly conductive layer ot india inl-1 or similar carbon-containing substance; it may be a thin paper strip coated with a highly resistant, exceedingly thin metal film. The

strip projects slightly beyond the ends of the stack 3, and its ends may be folded under the acent extremities of the clamps 1, and soldered or otherwise united thereto, along with the projecting tin toil ends, so that a good and durable Contact with the clamis lind the terminals of t-he condenser results.

ln the completed unit, compressed by tightening the clamps 1 and the clamp 10, the elastic cork plate 6 thus exerts steady pressure upon the resistance strip and prevents any displacement thereot which might possibly break or impair its connection with the terminals of the condenser.

ln some wireless circuits it is desirable now and then to connect the resistance element directly cross the grid lead and the filament lead, instead of between the condenser ter minals, as shown in Figure 1.

Figures 3 and l show a modification ot my grid leak and condenser, in which provision is made for connecting the resistance 8 into the circuit in such a way. Here only one end ot the strip 8 is joined to one terminal ot the condenser by securing it under the adjacent end of one of the clamps 1 and the other end can be united to a suitable conductor. rlhen the overlapping edge 1l of the other clamp 1 can be partly removed to permit suiiicient insulating space upon the surface ot plate 9 for the location of some form of suitable isolated terminal 12 to which one end ot the resistor c is atned under the plate 9, the other end olf the resistor S being connected to one of the clamps 1. ln the drawing l have illustrated this terminal 12 as being in the 'form of a compression headed screw or rivet -3, located in a suitable perforation in plate 9 and with its outer end riveted over the perforated end of a Vsuitable conductive clip connection 14 placed upon a short perforated conductor arm 15, rotatably mounted upon the riv t 18, and in contact therewith. At its tip, arm or switch member 15, has a knob le to enable the arn to be moved to engage with the cut away edge 11 ot the adjacent clamp. lllhen the arm 15 is thus turned to move it into contact with the clamp 1, the resistance 8 can thus be connected directly, if desired, across the terminals, 1, making the combination essentially the saine as that illustrated in 1. Between the clip 14 and the arm 15 is an insulating washer 1?. lVhen the arm 15 is separated :trom the clamp 11, a conductor can be secure to the clip 14, which also is in electrical contact with the rivet 13 to allow the resistance 8 to be put in circuit otherwise than by bridging it across the condenser es above. Any other convenient manner of insulating one end of the resistance 8 and adapt ing this end for connection with some other part ci a radio circuit, may be employed. VvThile l have shown and described the parts embodied in a preferred and in a modified form of my invention l wish it to be understood that l do not confine myself to the precise details ot construction as herein set forth; as it is apparent that many changes may be made by those skilled in the art within the broad meanings or" the terms in the appended claims.

Having described my invention, what I believe to be new and desire to secure and protect by Letters Patent ot the United States is 1. A condenser having sheets of conducting material separated by insulation, cover plates *for the condenser', clamps associated with the cover plates and forming terminals tor the condenser and a resistance element under one oi said plates to be connected at one end with a terminal ot the condenserV and serve as a grid leak.

2. A condenser having sheets of conducting material separated by insulation, cover plates for the condenser, clamps associated with said plates and constituting terminals tor the condenser, and a resistance element under one ot said plates and having its ends in contact with the two clamps to serve as a grid leak.

3. A condenser having sheets ot conducting material separated by insulation, cover plates tor the condenser, clamps associated with the cover plates and forming terminals for the condenser and a conductive element under one ot said plates to be connected at one end with a terminal oi' the condenser and serve as a grid leak, the condenser also carrying an isolated terminal to enable the other end ot' said element to be connected thereto, with a switch member on said terminal to make contact with the other clamp ot the condenser when desired.

l. A condenser comprising conductive elements separated by insulation, cover plates for the condenser, a plate ot compressive material under one cover plate; and having a groove therein, and a conductive element in said groove and thus disposed in thc body of the condenser.

5. A condenser having conductive sheets separated by dielectric material, a resistance element incorporated therein and connected to the terminals thereof, and switching means for vdisconnecting the resistance element from one of the terminals ot the condenser.

In testimony whereof l aiiix my signature.

j llLLIAli/l DUBlLlER. 

